Abstract

Various methods of absolute displacement measurement by means of optical interferometers have been presented in recent years^{[1] [2] [3]}. The existing methods are generally feasible in low speed measurement cases. However, in some high speed measurement cases, one can find hardly a suitable technique if the measurement accuracy requirement is high. The speed limitation in the absolute displacement measurement interferometers is mainly due to the usage of slow modulation(or scanning) technique. It is difficult to improve the present modulation techniques for the fast measurement. Here we propose an interferometer system scheme and explore a new absolute displacement measurement principle by doing the numerical study. According to the numerical study, the scheme proposed provides the possibility to acquire quickly the absolute displacement measurement data within a small displacement range.

© 1998 Optical Society of America